What is the recommended screening interval for mammography in women aged 50-74?

• A. Annually
• B. Every 3 years
• C. Every 5 years
• D. Every 2 years

Answer: (D)

For women at average risk, the aim of screening is to catch cancers early while minimizing harms from the test itself. Screening every two years achieves that balance for those aged 50–74: it preserves most of the mortality benefit seen in trials while reducing harms from false positives, unnecessary biopsies, and anxiety that come with more frequent testing. Annual screening provides only a modest additional mortality reduction compared with biennial screening but increases the cumulative harms; waiting three or more years risks missing cancers that could have been detected earlier, reducing potential benefit. For higher-risk individuals (e.g., strong family history or known genetic mutations), more intensive approaches may be appropriate, but for the average-risk 50–74 group, a biennial interval is recommended.